There are many species of jellyfish which can affect humans. The major Australian box jellyfish, Chironex fleckeri , is the only proven lethal species, for which there is an antivenom, but there are several other species which can cause severe, maybe lethal, reactions.

All jellyfish sting using individual stinging cells (nematocysts), and millions of these may discharge into a patient in a major jellyfish sting. Some of this venom may directly enter capillaries, so systemic envenoming can be very rapid indeed. Much less commonly, the venom may cause "allergic" type reactions in some people.

Pain is not a universal diagnostic feature of all jellyfish envenoming, though it is the most common symptom.

Irukandji syndrome

This important response to stings by several probably related species of small and virtually invisible, tropical jellyfish is typified by mild local pain, usually without skin marks. About 30 to 40 minutes later there may develop the typical syndrome of cramping muscle, back and abdominal pains, prostration, hypertension and occasionally, pulmonary or cardiac complications.

This is a most unpleasant condition and is potentially lethal. There is no antivenom. Hospitalisation is essential for the full blown syndrome. Early vinegar application is recommended for nematocyst inhibition.

Bluebottle, Physalia sp.

A medium sized "jellyfish" causing stings in northern and eastern Australian waters mainly, often in swarms. There is immediate pain lasting an hour or more, with typical elliptical blanched wheals and surrounding erythema. Mild or no systemic symptoms are usual, but a muscle-pain syndrome may occur.

There is no antivenom. Vinegar or water discharges adherent nematocysts.

Press: Release: Lifesavers launch campaign for jellyfish anti-venene

Surf Lifesaving Australia is trying to take the sting out of the Irukandji jellyfish. While Australia has an anti-venene for the box jellyfish and it's had one since 1966, Irukandji jellyfish have gone unchecked.

But John Taylor reports that the Surf Lifesavers have launched an intense campaign to unlock the jellyfish's secrets.

The box jellyfish is responsible for a recorded 66 deaths in Australia, and while netted beaches are commonplace in North Queensland, they don't keep Irukandji jellyfish out. Dr Peter Fenner, the national medical officer for Surf Lifesaving Australia, says while Irukandji may only be about the size of a thumb nail they have a fair sting.

People get severe back pains, cramps in their legs, the abdomen, their chest, their arms. They get severe anxiety, sweating, headaches, nausea, vomiting. They feel like death warmed up and it is most unpleasant. They feel like they're going to die.

For fourteen years Dr Fenner has recorded every Australian Irukandji sting. He's up to 660. Unlike the box jellyfish, there is no antivenene for Irukandji. But Dr Fenner says Surf Lifesaving Australia has won the support of a number of organisations to make one.

And between those, it's managed to get sufficient money to be able to bring a lady over from America who will actually be catching Irukandji for us in the Cairns area. She'll be netting for them regularly. She'll be identifying them as they come out. Some specimens will go to the University in California for sequencing of the DNA so we identify them very accurately and the ones that we have identified will be sent to the Australian Venom Research Unit where we hope to extract the venom and make an anti-venom.

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